Mast Cell Sarcoma with Megakaryocytic Differentiation in a Calf

Abstract

ABSTRACT. A case of mast cell sarcoma in a 5-month-old Holstein female calf is described. Macroscopically, enlargement of the spleen, lymph nodes, tonsils and kidneys was noted, and there were tumor masses in the neck region and on the pleura and peritoneum. The pericardium and uterine and ureter walls were also involved by tumor. Most neoplastic cells had eosinophilic granules, which were metachromatic and positive for naphthol AS-D chloroacetate esterase and tryptase, whereas smaller numbers of cells were positive for factor VIII-related antigen, a marker of megakaryocytes. Some of the predominant type of these tumor cells were found within the epithelia of the lungs, tonsils, gastrointestinal tract, liver, ureters, urinary bladder and uterus. Their normal counterparts were considered to be globule leukocytes. KEY WORDS: cattle, epitheliotropism, globule leukocyte, mast cell sarcoma.doi: 10.1292/jvms.12-0236; J. Vet. Med. Sci. 74(12): 1643-1646, 2012 Mast cell tumors in dogs are the most frequent malignant or potentially malignant tumor of the skin [7]. In humans, systemic mastocytosis is a disease caused by a neoplastic proliferation of mast cells. Most cases have the skin lesions of urticaria pigmentosa, and the majority of these have a relatively benign course [2]. In contrast, cases without skin lesions have a worse prognosis and may progress to transformation into mast cell leukemia or, more commonly, acute myeloblastic leukemia [9]. Highly malignant mast cell disorders such as mast cell leukemia and mast cell sarcoma are cytologically distinct from indolent systemic mastocytosis [2], and are not always associated with the mastocytosis [3].In cattle, mastocytoma is a benign or low malignancy neoplasm of mast cell origin, occurring chiefly in the skin [8]. Although multiple skin lesions or metastases in visceral organs are not infrequent, cutaneous mastocytomas are characterized by rare or absent mitotic figures [8]. Leukemias of the mast cell lineage [19] or with both mastocytic and megakaryocytic differentiation [10] have been observed in cattle. Here, we report, in a calf, a mast cell sarcoma that possessed mast cell features such as metachromasia and tryptase positivity, but also factor VIII-related antigen expression in a minority of cells.A 5-month-old Holstein female calf exhibited enlargement of the superficial lymph nodes, emaciation, growth retardation, rough hair coat and a rectal temperature of 40.5°C. The next day, hematological values were as follows: hematocrit, 17%; white blood cell count, 8,560 cells/ µl with 2% neutrophils, 43% lymphocytes, 1% monocytes and 54% atypical cells with nuclear irregularity and/or coarse azurophilic granules in the cytoplasm. Antibodies to bovine leukosis virus (BLV) were not detected by the agar gel immunodiffusion test. A clinical diagnosis of calf-form leukosis was made, and euthanasia was performed seven days after the initial examination.At necropsy, the superficial lymph nodes were highly to moderately enlarged, and were grayish white and homogeneous on c...

Neutrophilic Granulocytic Sarcoma and Acute Basophilic Leukemia in Cattle

“…In addition, the number of leukemia cells with granules was much larger than in the previous cases. Marked eosinophil infiltration is observed in bovine well-differentiated (Fujimoto et al 2012) but not in less-differentiated cutaneous mastocytoma (unpublished data). Mast cell degranulation causes the development of pulmonary fibrosis in humans (Veerappan et al 2013), and intestinal sclerosing mast cell tumors have been reported in cats (Halsey et al 2010).…”

“…An additional case has recently been reported to be composed of cells of the basophil series, based solely on the observation of purple intracytoplasmic granules in blood and bone marrow smears (Laabs et al 2015). Unfortunately, in that paper, basophil tumor cells could not be distinguished from malignant mast cells, which also contain granules staining purple with Giemsa (Ikehata et al 2011, Fujimoto et al 2012. In the present study, we report a case of neutrophilic granulocytic sarcoma and another of acute basophilic leukemia.…”

“…Additionally, normal basophils can be readily confused with neutrophils or eosinophils in cattle (Kawashima et al 2016) and cats (Fairley & Shackleton 2013). In contrast, Giemsa staining for histology is helpful in distinguishing between granules of basophil or mast cell neoplasms and those of neutrophilic or eosinophilic granulocytic leukemia, or granular T cell lymphomas (Takayama et al 1996, Nozaki et al 2006, Naitou et al 2007, Ikehata et al 2011, Fujimoto et al 2012.…”

“…However, large numbers of copies cannot always be linked to a diagnosis of BLV-associated lymphoma, since they may be observed also in healthy cattle infected with BLV (Chiba et al 2014). Likewise, a diagnosis of basophilic leukemia could not be established by demonstrating the presence of purple cytoplasmic granules in blood smears (Laabs et al 2015), because similar granules are also seen in malignant mast cell tumors (Ikehata et al 2011, Fujimoto et al 2012. Bilineal leukemia or sarcoma is not rare in cattle and swine (Kadota et al 1987, Ikehata et al 2011, Fujimoto et al 2012, and it is not easy to detect the secondary predominating lineage on blood smears.…”

“…In cattle, there are published cases of hematopoietic malignant neoplasia such as acute neutrophilic leukemia (Takayama et al 1996), acute mastocytic-megakaryocytic leukemia (Ikehata et al 2011), acute erythremic myelosis (pure erythroid leukemia) (Watanabe et al 1998), mast cell sarcoma (Fujimoto et al 2012), and histiocytic sarcoma (Anjiki et al 2000). The reported cases of monocytic leukemia (Mackey et al 1972), myelomonocytic leukemia (Woods et al 1993) and mast cell leukemia (Trautwein & Stӧber 1965) are devoid of convincing histological…”